Deputy Prime Minister Nick Clegg today came to the defence of Liberal Democrat MP David Laws amid reports that he is to be suspended from Parliament for seven days for breaching expenses rules.

Mr Clegg described Mr Laws as "a close friend and ... a very decent man", but refused to speculate on whether his return to Cabinet might be blocked if he is censured by the House of Commons standards watchdog tomorrow.

The Commons Standards and Privileges Committee will tomorrow release its eagerly-awaited report on Mr Laws's payment of thousands of pounds in parliamentary expenses in rent to his partner.

The BBC has reported that Mr Laws has been found guilty of "around six" breaches of the regulations by Parliamentary Commissioner for Standards John Lyon, and another report today said he will be required to apologise and face a seven-day suspension.

Mr Clegg today refused to comment on the content of the report, describing the apparent leaks as "totally unacceptable".

But he told Sky News: "David Laws is a very close friend of mine, a good colleague and a very decent man.

"He has always been very open about the fact that he made some mistakes. He resigned and paid money back.

"But what he has also said is that what happened was because he wanted to protect his privacy, he didn't want in any way to benefit from the expenses system, the taxpayer hasn't in any way lost out because of what happened, and I totally believe him."

Mr Laws quit the new coalition Government just 17 days after his appointment as a Treasury chief secretary following the disclosure that he claimed tens of thousands of pounds rent paid to his partner, lobbyist James Lundie.

Mr Laws, who referred himself to the commissioner, apologised at the time and admitted he had made a mistake after the Commons rules were changed in 2006 to bar such claims.

The commissioner's findings were considered yesterday at a meeting of MPs on the Standards and Privileges Committee.

Commons Speaker John Bercow today called for a probe into how details of the inquiry became public. If the findings had been leaked it was a "rank discourtesy", he said.

Mr Bercow was responding to a point of order in the Commons from deputy Lib Dem leader Simon Hughes, who said any leak was "clearly a breach of the rules of the House".

Mr Hughes said: "Everybody who breaches the rules must understand the implications of that when the matter is looked at both by you and by the relevant committees."

The Speaker responded: "At this juncture it is not specifically a matter for me but for the committee itself to investigate.

"It might wish to establish how this came about because it is something which I think all Members who care about this place would unite in deprecating in the strongest terms for the unfairness to the Member concerned and the rank discourtesy to the institution of the House of Commons."